Battery system



FIG. 1 is a front perspective view of a battery system of the present design;

FIG. 2 is a right view of the embodiment of FIG. 1;

FIG. 3 is a left view of the embodiment of FIG. 1;

FIG. 4 is a front view of the embodiment of FIG. 1;

FIG. 5 is a back view of the embodiment of FIG. 1;

FIG. 6 is a top view of the embodiment of FIG. 1; and,

FIG. 7 is a bottom view of the embodiment of FIG. 1. 

The ornamental design for a battery system, as shown and described. 